JP2014500466A - Cage holding ball and deep groove ball bearing for ball bearing - Google Patents

Abstract

  The present invention is a cage for a ball bearing unit and comprises two cage halves (51, 52) that are symmetrical with respect to the central plane (P) and connected to each other. Each cage half comprises an annular body (53). Each cage half comprises two concentric circumferentially continuous radial ridges (56, 57), with the first ridge (56) extending radially outwardly and extending outside the bearing unit. A groove (35) formed in the inner ring of the bearing unit is engaged with the groove (25) formed in the ring in a sealing manner, and the second ridge (57) extends radially inward. ) In a sealing manner.

Description

  The present invention relates to a cage for holding a ball for a ball bearing. The invention also relates to a deep groove ball bearing, as is known in the art by the abbreviation DGBB (deep groove ball bearing).

  A known bearing unit includes a cage holding a ball. The cage is composed of two symmetrical cage halves connected to each other. Each of the cage halves has interconnecting means for opposing cage halves and provides a plurality of partially spherical cavities. The plurality of partial spherical cavities face axisymmetrically with respect to the partial spherical cavities of the opposing cage halves. Thereby, a ball holding pocket is formed by a plurality of partially spherical cavities of both cage halves.

No prior art document is described in this specification.

  It is a general object of the present invention to provide a cage and bearing of the type described above, which makes the assembly procedure easier and even more economical. Another object of the present invention is to improve the seal and improve the degree of dispersion of the lubricating grease in the bearing unit.

  The above objects and other objects and advantages are obtained by the present invention by the cage as defined in claim 1, as will be clear from the following description. In another aspect of the invention, a bearing unit as defined in claim 14 is provided. Preferred embodiments of the invention are defined in the dependent claims. The claims are considered a part of this specification.

  Preferred embodiments that do not limit the present invention will be described below with reference to the accompanying drawings.

4 is an axial cross-section partially showing a bearing unit including a cage according to an embodiment of the present invention. FIG. 2 is an axial cross-section partially showing the outer ring of the bearing unit of FIG. 1. It is an enlarged view which shows the detail 2A in FIG. 2 in detail. It is an enlarged view which shows the detail 2B in FIG. 2 in detail. 2 is an axial cross-section partially showing an inner ring of the bearing unit of FIG. 1. It is an enlarged view which shows the detail 3A in FIG. It is a perspective view which shows the bearing unit of FIG. 1, and illustration of an outer ring is abbreviate | omitted for the simplification of illustration. It is a figure which shows the bearing unit of FIG. 4, and illustration of a part of cage is abbreviate | omitted. It is sectional drawing which shows the bearing unit of FIG. 1 along an axial direction plane.

  Prior to a detailed description of the embodiments of the present invention, it is emphasized that the present invention is not limited to the details and applications of each member described below and each member illustrated in the accompanying drawings. The present invention can be applied to various uses. The following terms are for illustrative purposes only and are not intended to limit the invention in any way. The use of the terms “having”, “having”, “forming”, etc. not only relates to the related member but also to the equivalent.

  First, as shown in FIG. 1, the ball bearing unit 10 is interposed between a fixed outer ring 20, an inner ring 30 that is rotatable around the rotation axis X, and the outer ring and the inner ring. A plurality of balls 40 forming a set and a cage 50 holding the balls are provided. The bearing unit 10 is a deep groove ball bearing (DGBB) unit.

  The cage 50 is composed of two cage halves 51 and 52 connected to each other. The cage halves are advantageously identical to one another and are arranged substantially symmetrically with respect to the radial central plane P passing through the bearing. On the radial center plane P, the centers C of the plurality of balls 40 are located. The cage half is preferably made of a plastic material such as PA66 (polyamide 66) or polyhexamethylenediamine. Such materials are already used for the production of holding cages. This is because even if it is frequently used, it is wear-resistant, because the coefficient of friction is small, and because the moldability is good, it is difficult to deteriorate. As an alternative material for the plastic material, for example, a metal material such as steel can be used.

  Because the cage halves are symmetrical, one member described and the other member not described are the same or substantially the same, so the following description will be made with respect to one member. . Each of the cage halves has a base annular body 53 having one side defining an axial outer surface in the situation where the cage is placed in a fully assembled bearing unit. Each of the cage halves forms a flat radial surface 54 on the axial outer surface. In use, the radial surface 54 is preferably arranged flush with the side surfaces 21 and 31 of the outer and inner rings. An annular groove 55 is formed at the center position in the axially outer surface of the cage half. As a result, the flexibility of the cage half can be further increased, and as will be described later, the cage half can be easily mounted on the bearing.

  Throughout this specification and throughout the claims, terms representing position and orientation, such as “axial” and “radial”, should be understood as relative to the rotational axis X of the bearing unit. .

  On the radially inner surface, the outer ring 20 has a central ball race 22. An intermediate annular groove 23 having a conical surface 24 (FIG. 2B) that deepens outward in the axial direction on both sides of the central ball race 22, and preferably a truncated cone shape (FIG. 2A) disposed outwardly in the axial direction of the bearing. ) Side annular grooves 25 are provided.

  The lateral annular groove 25 is aligned in the radial direction with respect to the lateral annular groove 35 (FIGS. 3 and 3A) formed on the radially outer surface of the inner ring on both sides of the inner ball race 32. .

  Each cage half has two radial ridges. The two radial ridges are substantially concentric and are continuous at the periphery. The first ridge 56 projects outward in the radial direction and engages with the side groove 25 formed in the outer ring to provide a labyrinth seal function. The second ridge 57 protrudes inward in the radial direction and engages with the side groove 35 formed in the inner ring in a sealing manner. The ridges 56 and 57 extend from the corresponding edges 58 and 59, respectively. The edges 58 and 59 protrude inward in the axial direction from the radially inner periphery and the radially outer periphery of the annular body 53. This configuration provides greater flexibility for the edges 58 and 59. This allows the two cage halves to be snapped into the mounting grooves 25, 35.

  On the inner side surface in the axial direction, the cage half has annular receptacles 60, 61 that open towards the ball. The function of the receptacles 60, 61 is to function as a reservoir for temporary accumulation of lubricating grease. The receptacle opens toward the ball. The conical surfaces 62, 63 of the receptacle are deeper towards the ball race. Thereby, the redispersion of the lubricating grease can be promoted toward the ball race and toward the intermediate groove 23.

  On the axial inner surface, in other words, on the surface facing the ball in use, the base annular body 53 of each cage half provides a plurality of partial spherical cavities 64. Each of the plurality of partial spherical cavities 64 is formed by a pair of axial protrusions 65 each having a concave surface 66. The concave surfaces 66 form the same ideal spherical surface, and face each other in pairs. The spherical seats of the two cage halves face each other in the axial direction in the assembled situation. The spherical seat forms a plurality of partial spherical pockets for holding the ball 40, evenly spaced between the races 22 and 32 of the bearing ring. Each pocket is a part of a spherical surface having its center C on the radial central plane P.

  In addition, a plurality of axial connection projections 67 extend from the inner surface in the axial direction of the base annular body 53 of each cage half. These protrusions 67 are alternately arranged with respect to the pair formed by the axial protrusions 65. Each of the connecting protrusions 67 has a plurality of spherical concave seats configured to form pockets for holding the ball in the assembled condition. On both sides of the concave seat 68, in the circumferential direction, each connecting projection has an interconnecting means for connecting to the opposing cage half. In the particular embodiment shown, the interconnecting means consists of an axially projecting pin 69 and a corresponding recess 70 which can advantageously snap lock the pin 69.

  As shown in FIG. 4, in the assembled state, the axial end surfaces of the protrusions 65 and 67 are in contact with each other and are located in the radial center plane P of the bearing.

  Each cage half has a circumferentially continuous portion 72 between the two projections 65, 67. The portion 72 extends in the axial direction from the axial inner surface of the base annular body of the cage half. The extension length of the portion 72 is shorter than the extension length of the protrusions 65 and 67 in the axial direction. The portion 72 is in the preferred embodiment of a trapezoidal pyramid shape and is axially shorter than the other protrusions 65, 67, and thus in combination with and opposite the other protrusions 65, 67. Combined with a similar configuration of halves, a plurality of radial passages 73 are formed. These passages provide fluid communication directly between the annular space disposed between the cage and the inner ball race to the annular space disposed between the cage and the outer ball race. Both annular spaces are filled with lubricating grease, as is known.

  The portion 72 has an obliquely inclined surface 74 provided as an inclined pair so as to facilitate the distribution of the lubricating grease in the bearing, thereby ensuring the distribution of the lubricating grease. . Thereby, it becomes large outward in the axial direction. The inclined surface 74 is slightly concave so that the flow of the lubricating grease can be further promoted based on the centrifugal force generated during the rotation of the cage.

  As will be appreciated, the presence of a cage that functions as a seal member to prevent the outflow of lubricating grease and of the cage that functions as a seal member to prevent inflow of contaminants into the bearing. Thanks to the presence, the two sealing shields conventionally provided on both sides of the bearing for the purpose of sealing the annular gap between the inner and outer rings of the bearing can be omitted. Due to the ridges 56, 57 formed by the cage halves, the bearing unit can advantageously be constructed without the need for any other special sealing means.

  Since it is not necessary to provide two shielding shields, manufacturing time, manufacturing cost, assembly time, and assembly cost can be directly reduced. Further cost reduction, material saving and weight reduction can be obtained. This is because the outer diameter of the inner ring can be reduced when forming the space necessary to accommodate each cage half, especially in the region where the mounting groove 25 for the cage half is formed. Corresponding material savings and weight savings are also obtained in the outer ring of the bearing. The inner diameter of the outer ring increases in the lateral region. Thereby, the radially outer member of the cage half can be received.

10 ball bearing unit 20 outer ring 22 radially outer race 25 groove 30 inner ring 32 radially inner race 35 groove 40 ball 50 cage 51 cage half 52 cage half 53 annular body 55 annular groove 56 radial ridge, first ridge 57 radial ridge, second ridge 58 edge 59 edge 60 annular receptacle 61 annular receptacle 62 conical surface 63 conical surface 64 partial spherical cavity 65 axial projection, first axial projection 66 concave surface, partial spherical cavity 67 axial projection, Second axial projection 68 Partial spherical cavity 69 Connecting means, pin 70 Connecting seat, recess 72 Partial 73 Radial passage 74 Inclined surface C center P Radial center plane

Claims (17)

A cage for a ball bearing unit,
A plurality of pockets forming a spherical surface having a center (C) in a radial central plane (P) of the bearing;
-Two cage halves (51, 52) symmetrical about said central plane (P) and connected to each other, each cage half comprising an annular body (53) and a plurality of partially spherical cavities (64, 66); 68), and the partial spherical cavity of one cage half is axially opposed to the partially spherical cavity of the other opposite cage half, thereby forming said pocket Two cage halves (51, 52);
-Connecting means (69, 70) provided in each cage half for connecting the two cage halves together;
Comprising
Each cage half (51, 52) comprises two concentric circumferentially continuous radial ridges (56, 57);
The radial ridges extend radially from the annular body (53) in opposite directions,
A first ridge (56) of the radial ridges extends radially outward and sealably engages a groove (25) formed in an outer ring of the bearing unit;
A second ridge (57) of the radial ridges extends radially inward and sealably engages with a groove (35) formed in the inner ring of the bearing unit. Features a cage. The cage of claim 1,
The first ridge (56) extends from an edge (58) protruding inward in the axial direction from a radially outer peripheral edge portion of the annular body (53),
The cage, wherein the second ridge (57) extends from an edge (59) projecting inward in the axial direction from a radially inner peripheral edge portion of the annular body (53). The cage of claim 2,
Each of the cage halves (51, 52) has two concentric annular receptacles (60, 61) that open towards the central plane (P);
The annular receptacle is restrained by the edges (58, 59);
A cage wherein the annular receptacle functions as a reservoir for lubricating grease. The cage of claim 3,
Each of said annular receptacles (60, 61) has a conical surface (62, 63) formed by said edge (58, 59);
Cage characterized in that the conical surface is deepened towards the central plane (P). The cage according to any one of claims 1 to 4,
A plurality of axial projections (65, 67) forming a plurality of partially spherical cavities extend from the annular body (53) of each cage half (51, 52) towards the central plane (P). And
At least some of the protrusions (65, 67) are connected by a portion (72);
The axial length of this portion (72) is shorter than the axial length of the protrusion,
Cage characterized in that said part (72), which is made short, forms a plurality of radial passages (73) together with opposing cage halves. The cage of claim 5,
Cage characterized in that said part (72), which has been shortened, has a pair of inclined surfaces (74), thereby deepening axially outwards. The cage of claim 6,
Cage characterized in that the inclined surface (74) is concave. The cage according to any one of claims 5 to 7,
Cage characterized in that the part (72), which is made short, has a trapezoidal pyramid shape. The cage according to any one of claims 1 to 8,
A plurality of axial projections (65, 67) forming a plurality of partial spherical cavities extend from a surface of the annular body (53) facing the central plane (P),
A plurality of axial projections (65, 67) forming a plurality of partial spherical cavities comprise a plurality of first axial projections (65) and a plurality of second axial projections (67),
The plurality of first axial protrusions (65) have a plurality of concave surfaces (66) positioned in the same ideal spherical surface while facing each other in pairs,
The plurality of second axial protrusions (67) are larger in the peripheral direction than the plurality of first axial protrusions (65),
The plurality of first axial protrusions (65) and the plurality of second axial protrusions (67) are alternately arranged,
The protrusions (67) form a plurality of spherical cavities;
A cage characterized in that a connecting means (69) or a connecting seat (70) is provided on both sides of these cavities in the peripheral direction for mutual connection of opposing cage halves. The cage according to claim 1 or 9,
The interconnection means has a pin (69) protruding in the axial direction;
Cage characterized in that the connecting seat (70) has a corresponding recess for snap-locking the pin (69). The cage of claim 10,
The cage characterized in that the pin (69) is an elastic bifurcated member. The cage of claim 9,
The axial protrusions (65, 67) have axial end surfaces located in the radial central plane (P);
A cage characterized in that the axial end surfaces of the axial projections of the cage halves facing each other are in contact with each other at the central plane. The cage of claim 2,
An annular groove (55) is formed on the axially outer surface of the annular body of the cage half;
The cage, wherein the annular groove is located in the middle of the radially outer peripheral edge portion and the radially inner peripheral edge portion in the radial direction. Especially a ball bearing unit (10) such as a deep groove type ball bearing unit,
An outer ring (20) having a radially inner surface providing a radially outer race (22);
An inner ring (30) having a radially outer surface that provides a radially inner race (32);
A plurality of balls (40) forming a set interposed between the radially outer race (22) and the radially inner race (32) in the radial direction;
Comprising
The bearing unit comprises a cage (50) according to any one of claims 1 to 13,
Each of the cage halves (51, 52) includes a first ridge (56) located on the radially outer side and a second ridge (57) located on the radially inner side,
The first ridge engages with a circumferential groove (25) formed on the radially inner surface of the outer ring (20) to provide a labyrinth seal action;
The bearing unit characterized in that the second ridge engages with a circumferential groove (35) formed on the radially outer surface of the inner ring (30) to provide a labyrinth sealing action. The bearing unit according to claim 14,
The outer ring (20) has an intermediate annular groove (23) between the race (22) and the groove (25) on both sides of the race (22). Bearing unit. The bearing unit according to claim 15,
Bearing unit characterized in that the intermediate annular groove (23) has a conical surface (24) deepening radially outward. The bearing unit according to claim 15 or 16,
The intermediate annular groove (23) is disposed adjacent to the conical surface (62) of the edge (58) in the axial direction, thereby receiving lubricating grease from the receptacle (60); A bearing unit characterized by

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